Abstract： Objective To explore the effect of thymosin alpha-1 combined with voriconazole in sequential treatment of patients with chronic obstructive pulmonary disease(COPD)and invasive pulmonary aspergillosis(IPA)and the impacts on cellular immune function in peripheral blood and inflammatory factor levels.Methods According to different treatment methods,a total of 108 patients with COPD and IPA who were admitted to the hospital from January 2020 to December 2023 were divided into the control group and the observation group,with 54 patients in each group.Both groups were given conventional symptomatic treatment.The control group was treated with voriconazole and the observation group was treated with thymosin alpha-1 combined with voriconazole.The two groups were compared on efficacy,cellular immune function in peripheral blood(CD3+,CD4+,CD8+and CD4+/CD8+),the levels of inflammatory factors[interleukin(IL)-6,IL-8,tumor necrosis factor-α(TNF-α)],and ad-verse reactions.Results The total effective rate of the observation group(96.3％)was significantly higher than that of the control group(81.5％)(x2=4.594,P=0.032).After treatment,the values of CD3+,CD4+and CD4+/CD8+in the observation group[(62±7)％,(44±5)％and(2.4±0.6)]were significantly higher than those in the control group[(51±7)％,(37±5)％and(2.0±0.6)](t=8.190,7.254,3.290,all P＜0.05).The level of CD8+in the ob-servation group[(20±3)％]was significantly lower than that in the control group[(27±3)％](t=10.658,P＜0.05).After treat-ment,the levels of IL-6,IL-8 and TNF-α in the observation group[(27±4)ng/L,(31±6)ng/L and(45±6)ng/L]were significantly lower than those in the control group[(32±4)ng/L,(37±5)ng/L and(53±6)ng/L](t=7.117,6.981,6.586,all P＜0.05).There was no statistically significant difference in the incidence of adverse reactions between the two groups(7.4％vs 14.8％,x2=0.787,P=0.375).Conclusion Compared to treatment with voricona-zole alone,sequential treatment with thymosin alpha-1 and voriconazole is more effective for patients with COPD and IPA.It can effectively improve the patients'immune function and reduce inflammatory reactions,with good clinical safety.